Refusing to be drawn into a controversy over Bihar governor Buta Singh clipping the wings of his Advisor Arun Pathak, Railway Minister and Rashtriya Janata Dal chief Lalu Prasad Yadav on Saturday said it was the governor's 'prerogative'.

"It is the Governor's prerogative. Pathak is his advisor," Lalu told reporters in Delhi when asked about Singh's move.He added that Pathak had not been removed from his post and continued to remain the governor's advisor.

Amid the controversy over his letter to the railway minister, seeking transfer of an official, Singh stripped Pathak, of his official powers by withdrawing key departments, including home, finance, power and personnel.